1. Ions and Ionic Bonding
7.1, 7.2, 9.1, 9.2

2. Objectives Ions (7.1) Ionic bonds and ionic compounds (7.2)
Naming Ions (9.1)
Naming and Writing Formulas for Ionic Compounds (9.2)

3. Ions

4. Valence electrons
The electrons in the highest occupied energy level of an element’s atoms.
How do we determine the number of valence electrons?

5. Ask about Magnesium, Boron, Helium, Fluorine

6. Octet Rule
In forming compounds, atoms tend to achieve the electrons configuration of a noble gas.
An octet does mean a set of 8, but REMEMBER, it does NOT mean an atom wants 8 electrons in its principal energy level- wants to achieve a noble-gas configuration
Atoms of metals lose electrons
Atoms of nonmetals gain electrons
Noble gases (except helium) have 8 electrons in their highest energy levels
The octet rule takes its name from this fact about noble gases.
How many electrons does barium have to give up to achieve a noble-gas configuration? -2
How does calcium obey the octet rule when reacting to form compounds?
-gives up electrons

7. Ions- Cations
Cations- positively charged ion produced when an atom loses one or more valence electrons
Cation = name of the element
Ca2+ = calcium ion

8. Ions- Anions
Anions- negatively charged particle produced when an atom gains one or more valence electrons
Anion = root + -ide
Cl- = chloride
What is the correct name for the N 3- ion?
-nitride ion

9. What is the charge of strontium?
-+2
What are examples of elements that form an ion with a 1- charge?
-Fluorine, chlorine, bromine, iodine

10. Ionic Compounds
An ionic compound is a compound composed of cations and anions.
Ionic compounds are electrically neutral which means
Total positive charge on cations = total negative charge on anions

11. Ionic Bonds
The electrostatic forces that binds oppositely charged ions together.
Atoms transfer valence electrons from metal to non-mental or cation to anion
What occurs in an ionic bond?
-oppositely charged ions attract
How many valence electrons are transferred from the calcium atom to iodine?
- 2

12. Writing Ionic Compounds
Use chemical formula to write the name of compounds
The formula unit is the lowest whole-number ratio of ions in an ionic compound.
Examples : NaCl, CaO, K2O
Mg2+ Cl MgCl2
K Cl KCl
Al O Al2O3

13. Properties of Ionic Compounds
Most ionic compounds are crystalline solids are room temperature.

14. Properties of Ionic Compounds
Ionic compounds can conduct an electric current when melted or dissolved in water because their ions are free to move about in the solution.

15. Naming Monatomic Ions
A single atom with positive or negative charge resulting from the loss or gain of one or more valence electrons
Differentiate between how to get the charges for metals and nonmetals to form their respective cations and anions.

16. What about the Transition Metals?
Form more than one cation with different ionic charges.
The charges of the cations of transition metals are determined from the number of electrons lost.

17. How do we name them? Stock system
Place a Roman numeral in parentheses after the name of he element to indicate the numerical value of the charge.
Fe+2
Lead (II) ion
Iron (II) ion
Pb+2

18. Binary Ionic Compounds
Compound composed of two elements with cation on left and anion on right
If the metallic element in the compound has more than one common ionic charge, a Roman numeral must be included in the cation name.
Iron (III) Oxide
PbO
Sodium Sulfide
Na3N

19. Practice What is the formula unit: Magnesium Chloride
Potassium Chloride
Aluminum Oxide

20. Practice Sodium Sulfide Na3N Copper (II) Sulfide CoI2 Aluminum Oxide
Li2Se